It has long been a problem to properly support paper machine shower pipes, which may extend twenty or thirty feet across the Fourdrinier wire of a typical paper machine. Such pipes must usually be of greater diameter and greater wall thickness than necessary for hydraulic capacity in order to provide the necessary structural strength to avoid sag or breakage.
In U.S. Pat. No. 2,884,203 to Broughton of Apr. 28, 1959, sagging due to the weight of a shower pipe is countered by a pair of tension rods, or braces, anchored to the casting of the brackets and each extending out to the center of the pipe.
In U.S. Pat. No. 3,279,976 to Eagle of Oct. 18, 1966, the shower pipe is given additional rigidity by a hollow hood extending across the machine above the pipe and fixed at each end to the end brackets.
In U.S. Pat. No. 3,161,125 to Hornboutel of Dec. 15, 1964, a hollow shell of a crown roll is given rigidity by an elongated shaft extending through the shell, the bearings for the opposite ends of the shaft tending to prevent sag of the shell by reason of an annular collar on the shaft supporting the shell against central deflection.